Sweet Talk: A Theory of Persuasion

This paper introduces a model of sweet talk in which a seller may acquire verifiable information and selectively disclose it to a buyer to negotiate a deal. We start by analyzing a model with common priors in which the seller generates information for two reasons: a trading motive and a profit motive that is, to make trade possible or to increase the gains from it. There exists a negotiation region in which the seller continues to reveal information even if trading is already profitable. We extend the model, allowing for different prior beliefs about the value of the object, arguing that a complementarity between the seller's confidence and the precision of his information endogenously arises. Appointing an optimistic salesman may be costly because he may destroy profitable trading opportunities. We also allow the seller to choose in which market to trade: a matching market with a fixed price or a haggling market. Our model also provides a testable difference between a model of trading with homogenous priors and one with heterogeneous priors and finds application in understanding contracts as reference points.persuasion games; haggling; negotiation; bargaining; heterogeneous priors, overconfidence, consummate and perfunctory performance, verifiable information.

Simbol-X capability of detecting the non-thermal emission of stellar flares

We investigate the capability of detecting, with Simbol-X, non-thermal emission during stellar flares, and distinguishing it from hot thermal emission. We find that flare non-thermal emission is detectable when at least ~20 cts are detected with the CZT detector in the 20-80 keV band. Therefore Simbol-X will detect the non-thermal emission from some of the X-ray brightest nearby stars, whether the thermal vs. non-thermal relation, derived for solar flares, holds.Comment: 2 pages, 2 postscript figures, proceedings of the workshop "Simbol-X: the hard X-ray universe in focus", to be published in "Memorie of the Italian Astronomical Society

Study made of large amplitude fuel sloshing

Study of resonant oscillations of an ideal fluid in a cylindrical tank is used to obtain a better understanding of fuel sloshing in large liquid booster. More realistic structural design criteria may be formulated when the dynamic response of the liquid in a cylindrical tank can be predicted analytically

A physical activity program dedicated to adolescents

Adolescence is a life stage in which the development ofindividuality and self-identity occurs.The recent study of the SIP evaluated the life style inadolescents, highlighting thelow participation to conti-nuative sports programs and the high incidence tosports drop out, interesting more than 30% of adoles-cents. These problems are partially linked to low com-pliance of adolescents to coaches training, partially tothe request of a sport close to adolescents requirements.However sports participation is beneficial for physicaland psychological development of adolescents. Sports pro-grams promote responsible social behaviours and greateracademic success, confidence in personal physical abilities,appreciation of personal health and fitness and strongsocial bonds with individuals and institutions. Adolescentsinvolved in physical activities fare better academically,have higher relationship skills, are more team-orientedand are healthier as determined by fitness standards.For these reasons the program of the physical activitydedicated to the adolescent needs a personal evaluation ofown desires and personal abilities, with a daily promotionof an active life style, preferring group activities (to go toschool and to come back home by foot or by bike withfriends, to walk for familial needs, etc.). The sport choicemust be carried out together with them, in order to guar-antee a four times a week physical activity, in conformitywith scholastic needs. Once a week they need to have spe-cial physical activities in accordance to familial requests.The skills of this program are: the education to amaintained physical assignment; the prevention of socialdeviation and/or alcohol, smoke, drugs dependence; theeducation to roles and rules, responsibilities, loyalty,cooperation, friendship

Discrete-time dynamic modeling for software and services composition as an extension of the Markov chain approach

Discrete Time Markov Chains (DTMCs) and Continuous Time Markov Chains (CTMCs) are often used to model various types of phenomena, such as, for example, the behavior of software products. In that case, Markov chains are widely used to describe possible time-varying behavior of “self-adaptive” software systems, where the transition from one state to another represents alternative choices at the software code level, taken according to a certain probability distribution. From a control-theoretical standpoint, some of these probabilities can be interpreted as control signals and others can just be observed. However, the translation between a DTMC or CTMC model and a corresponding first principle model, that can be used to design a control system is not immediate. This paper investigates a possible solution for translating a CTMC model into a dynamic system, with focus on the control of computing systems components. Notice that DTMC models can be translated as well, providing additional information

A note on the birefringence angle estimation in CMB data analysis

Parity violating physics beyond the standard model of particle physics induces a rotation of the linear polarization of photons. This effect, also known as cosmological birefringence (CB), can be tested with the observations of the cosmic microwave background (CMB) anisotropies which are linearly polarized at the level of $5-10\%$. In particular CB produces non-null CMB cross correlations between temperature and B mode-polarization, and between E- and B-mode polarization. Here we study the properties of the so called D-estimators, often used to constrain such an effect. After deriving the framework of both frequentist and Bayesian analysis, we discuss the interplay between birefringence and weak-lensing, which, albeit parity conserving, modifies pre-existing TB and EB cross correlation.Comment: 12 pages. Accepted for publication in JCA

GWGW vertex corrected calculations for molecular systems

Hedin's scheme is solved with the inclusion of the vertex function ($GW\Gamma$) for a set of small molecules. The computational scheme allows for the consistent inclusion of the vertex both at the polarizability level and in the self-energy. A diagrammatic analysis shows that the self-energy formed with this four-point vertex does not lead to double counting of diagrams, that can be classified as direct "bubbles" and exchange diagrams. By removing the exchange diagrams from the self-energy, a simpler approximation is obtained, called $GW^{\rm{tc-tc}}$. Very good agreement with expensive wavefunction-based methods is obtained for both approximations.Comment: 27 pages, 8 figure

Households’ Indebtedness and Financial Fragility

The paper studies the determinants of international differences in household indebtedness, and inquires whether indebtedness is associated with increased “financial fragility”, as measured by the sensitivity of household arrears and insolvencies to macroeconomic shocks. It also investigates whether financial fragility is affected by institutional factors, such as information sharing arrangements, judicial efficiency and individual bankruptcy regulation. We address these issues by tapping three data sets: (i) cross-country data on household indebtedness; (ii) European panel data for households lending and arrears; and (iii) time series data for household lending and insolvencies in the U.K., the U.S.A. and Germany. Overall, the analysis underscores the importance of institutional arrangements in determining the size and fragility of household credit markets.household debt, financial fragility, arrears, insolvency, information sharing, judicial efficiency, bankruptcy law